Acetylenes disubstituted with a 5-amino or substituted 5-amino substituted tetrahydronaphthyl group and with an aryl or heteroaryl group having retinoid-like biological activity

ABSTRACT

Compounds of the formula ##STR1## having retinoid like biological activity.

1. Field of the Invention

The present invention relates to novel compounds having retinoid-likeactivity. More specifically, the present invention relates to compoundshaving an acetylene portion which is substituted with a 5-amino orsubstituted 5-amino substituted tetrahydronaphthyl and by a substitutedaryl or substituted heteroaryl group having an acid function. The acidfunction may also be converted to an alcohol, aldehyde or ketone orderivatives thereof, or may be reduced to --CH₃.

2. Background Art

Compounds which have retinoid-like activity are well known in the art,and are described in numerous United States and other patents and inscientific publications. It is generally known and accepted in the artthat retinoid-like activity is useful for treating animals of themammalian species, including humans, for curing or alleviating thesymptoms and conditions of numerous diseases and conditions. In otherwords, it is generally accepted in the art that pharmaceuticalcompositions having a retinoid-like compound or compounds as the activeingredient are useful as regulators of cell proliferation anddifferentiation, and particularly as agents for treating skin-relateddiseases, including, actinic keratoses, arsenic keratoses, inflammatoryand non-inflammatory acne, psoriasis, ichthyoses and otherkeratinization and hyperproliferative disorders of the skin, eczema,atopic dermatitis, Darriers disease, lichen planus, prevention andreversal of glucocorticoid damage (steroid atrophy), as a topicalanti-microbial, as skin anti-pigmentation agents and to treat andreverse the effects of age and photo damage to the skin. Retinoidcompounds are also useful for the prevention and treatment of cancerousand precancerous conditions, including, premalignant and malignanthyperproliferative diseases such as cancers of the breast, skin,prostate, cervix, uterus, colon, bladder, esophagus, stomach, lung,larynx, oral cavity, blood and lymphatic system, metaplasias,dysplasias, neoplasias, leukoplakias and papillomas of the mucousmembranes and in the treatment of Kaposi's sarcoma. In addition,retinoid compounds can be used as agents to treat diseases of the eye,including, without limitation, proliferative vitreoretinopathy (PVR),retinal detachment, dry eye and other corneopathies, as well as in thetreatment and prevention of various cardiovascular diseases, including,without limitation, diseases associated with lipid metabolism such asdyslipidemias, prevention of post-angioplasty restenosis and as an agentto increase the level of circulating tissue plasminogen activator (TPA).Other uses for retinoid compounds include the prevention and treatmentof conditions and diseases associated with human papilloma virus (HPV),including warts and genital warts, various inflammatory diseases such aspulmonary fibrosis, ileitis, colitis and Krohn's disease,neurodegenerative diseases such as Alzheimer's disease, Parkinson'sdisease and stroke, improper pituitary function, including insufficientproduction of growth hormone, modulation of apoptosis, including boththe induction of apoptosis and inhibition of T-Cell activated apoptosis,restoration of hair growth, including combination therapies with thepresent compounds and other agents such as Minoxidil®, diseasesassociated with the immune system, including use of the presentcompounds as immunosuppressants and immunostimulants, modulation oforgan transplant rejection and facilitation of wound healing, includingmodulation of chelosis.

U.S. Pat. Nos. 4,740,519 (Shroot et al.), 4,826,969 (Maignan et al.),4,326,055 (Loeliger et al.), 5,130,335 (Chandraratna et al.), 5,037,825(Klaus et al.), 5,231,113 (Chandraratna et al.), 5,324,840(Chandraratna), Published European Patent Application Nos. 0 176 034 A(Wuest et al.), 0 350 846 A (Klaus et al.), 0 176 032 A (Frickel etal.), 0 176 033 A (Frickel et al.), 0 253 302 A (Klaus et al.), 0 303915 A (Bryce et al.), UK Patent Application GB 2190378 A (Klaus et al.),German Patent Application Nos. DE 3715955 A1 (Klaus et al.), DE 3602473A1 (Wuest et al., and the articles J. Amer. Acad. Derm. 15: 756-764(1986) (Sporn et al.), Chem. Pharm. Bull. 33: 404-407 (1985) (Shudo etal.), J. Med Chem. 1988 31, 2182-2192 (Kagechika et al.), Chemistry andBiology of Synthetic Retinoids CRC Press Inc. 1990 p 334-335, 354(Dawson et al.), describe or relate to compounds which include atetrahydronaphthyl moiety and have retinoid-like or related biologicalactivity. U.S. Pat. No. 4,391,731 (Boller et al.) describestetrahydronaphthalene derivatives which are useful in liquid crystalcompositions. Several co-pending applications and recently issuedpatents which are assigned to the assignee of the present application,are directed to further compounds having retinoid-like activity.

SUMMARY OF THE INVENTION

The present invention covers compounds of Formula ##STR2## wherein R₁ ishydrogen or alkyl of 1 to 10 carbons;

R₂ and R₃ are hydrogen, or alkyl of 1 to 6 carbons and the substitutedethynyl group occupies either the 2 or the 3 position of thetetrahydronaphthalene nucleus;

m is an integer having the value of 0-3;

o is an integer having the value 0-4;

Y is a phenyl group, or heteroaryl selected from a group consisting ofpyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl,oxazolyl, and imidazolyl, said groups being optionally substituted withone or two R₂ groups;

A is (CH₂)_(n) where n is 0-5, lower branched chain alkyl having 3-6carbons, cycloalkyl having 3-6 carbons, alkenyl having 2-6 carbons and 1or 2 double bonds, alkynyl having 2-6 carbons and 1 or 2 triple bonds;

B is hydrogen, COOH or a pharmaceutically acceptable salt thereof,COOR₈, CONR₉ R₁₀, --CH₂ OH, CH₂ OR₁₁, CH₂ OCOR₁₁, CHO, CH(OR₁₂)₂,--CHOR₇, CR₇ (OR₁₂)₂, CR₇ OR₁₃ O, or tri-lower alkylsilyl, where R₇ isan alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons, R₈ isan alkyl group of 1 to 10 carbons or trimethylsilylalkyl where the alkylgroup has 1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, orR₈ is phenyl or lower alkylphenyl, R₉ and R₁₀ independently arehydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group of5-10 carbons, or phenyl or lower alkylphenyl, R₁₁ is lower alkyl, phenylor lower alkylphenyl, R₁₂ is lower alkyl, and R₁₃ is divalent alkylradical of 2-5 carbons, and

R₁₄ is hydrogen, alkyl of 1 to 10 carbons, alkenyl of 2 to 10 carbonsand having 1 to 3 double bonds, alkynyl having 2 to 10 carbons and 1 to3 triple bonds, carbocyclic aryl selected from the group consisting ofphenyl, C₁ -C₁₀ -alkylphenyl, naphthyl, C₁ -C₁₀ -alkylnaphthyl,phenyl-C₁ -C₁₀ alkyl, naphthyl-C₁ -C₁₀ alkyl, or R₁₄ is COR₈, or the twoR₁₄ groups together with the N jointly form a 5 or 6 membered ring.

In a second aspect, this invention relates to the use of the compoundsof Formula 5 for the treatment of skin-related diseases, including,without limitation, actinic keratoses, arsenic keratoses, inflammatoryand non-inflammatory acne, psoriasis, ichthyoses and otherkeratinization and hyperproliferative disorders of the skin, eczema,atopic dermatitis, Darriers disease, lichen planus, prevention andreversal of glucocorticoid damage (steroid atrophy), as a topicalanti-microbial, as skin anti-pigmentation agents and to treat andreverse the effects of age and photo damage to the skin. The compoundsare also useful for the prevention and treatment of cancerous andprecancerous conditions, including, premalignant and malignanthyperproliferative diseases such as cancers of the breast, skin,prostate, cervix, uterus, colon, bladder, esophagus, stomach, lung,larynx, oral cavity, blood and lymphatic system, metaplasias,dysplasias, neoplasias, leukoplakias and papillomas of the mucousmembranes and in the treatment of Kaposi's sarcoma. In addition, thepresent compounds can be used as agents to treat diseases of the eye,including, without limitation, proliferative vitreoretinopathy (PVR),retinal detachment, dry eye and other corneopathies, as well as in thetreatment and prevention of various cardiovascular diseases, including,without limitation, diseases associated with lipid metabolism such asdyslipidemias, prevention of post-angioplasty restenosis and as an agentto increase the level of circulating tissue plasminogen activator (TPA).Other uses for the compounds of the present invention include theprevention and treatment of conditions and diseases associated withHuman papilloma virus (HPV), including warts and genital warts, variousinflammatory diseases such as pulmonary fibrosis, ileitis, colitis andKrohn's disease, neurodegenerative diseases such as Alzheimer's disease,Parkinson's disease and stroke, improper pituitary function, includinginsufficient production of growth hormone, modulation of apoptosis,including both the induction of apoptosis and inhibition of T-Cellactivated apoptosis, restoration of hair growth, including combinationtherapies with the present compounds and other agents such asMinoxidil®, diseases associated with the immune system, including use ofthe present compounds as immunosuppressants and immunostimulants,modulation of organ transplant rejection and facilitation of woundhealing, including modulation of chelosis.

This invention also relates to a pharmaceutical formulation comprising acompound of Formula 5 in admixture with a pharmaceutically acceptableexcipient.

In another aspect, this invention relates to processes for making acompound of Formula 5 which process comprises reacting a compound ofFormula 8 with a compound of Formula 9, in the presence of cuprousiodide and Pd(PQ₃)₂ Cl₂ (Q is phenyl) or a similar complex, or reactingthe zinc salt of the compound shown in Formula 8 with a compound ofFormula 9 in the presence of Pd(PQ₃)₄ (Q is phenyl) or similar complex.In Formula 8 the symbol STHN (substituted tetrahydronaphthyl) representsa tetrahydronaphthalene nucleus which is appropriately substituted toprovide the compounds defined in Formula 5 or said tetrahydronaphthalenenucleus is appropriately substituted to provide such precursors ofcompounds of the Formula 5 from which the target compounds can bereadily obtained by organic reactions well known in the art. In Formula9 X₁ is halogen, B' is H, or a protected acid, alcohol, aidehyde, orketone. In effect, B' is either the desired B group of Formula 5 or B'is a precursor from which the B group can be readily obtained byreactions well known in the art. ##STR3##

Still further, the present invention relates to such reactions performedon the compounds of Formula 5 which cause transformations of the A-Bgroup or of the substituents on the tetrahydronaphthalene moiety, whilethe reaction product still remains within the scope of Formula 5.

GENERAL EMBODIMENTS Definitions

The term alkyl refers to and covers any and all groups which are knownas normal alkyl, branched-chain alkyl and cycloalkyl. The term alkenylrefers to and covers normal alkenyl, branch chain alkenyl andcycloalkenyl groups having one or more sites of unsaturation. Similarly,the term alkynyl refers to and covers normal alkynyl, and branch chainalkynyl groups having one or more triple bonds.

Lower alkyl means the above-defined broad definition of alkyl groupshaving 1 to 6 carbons in case of normal lower alkyl, and as applicable 3to 6 carbons for lower branch chained and cycloalkyl groups. Loweralkenyl is defined similarly having 2 to 6 carbons for normal loweralkenyl groups, and 3 to 6 carbons for branch chained and cyclo- loweralkenyl groups. Lower alkynyl is also defined similarly, having 2 to 6carbons for normal lower alkynyl groups, and 4 to 6 carbons for branchchained lower alkynyl groups.

The term "ester" as used here refers to and covers any compound fallingwithin the definition of that term as classically used in organicchemistry. It includes organic and inorganic esters. Where B (of Formula5) is --COOH, this term covers the products derived from treatment ofthis function with alcohols or thiols preferably with aliphatic alcoholshaving 1-6 carbons. Where the ester is derived from compounds where B is--CH₂ OH, this term covers compounds derived from organic acids capableof forming esters including phosphorous based and sulfur based acids, orcompounds of the formula --CH₂ OCOR₁₁ where R₁₁ is any substituted orunsubstituted aliphatic, aromatic, heteroaromatic or aliphatic aromaticgroup, preferably with 1-6 carbons in the aliphatic portions.

Unless stated otherwise in this application, preferred esters arederived from the saturated aliphatic alcohols or acids of ten or fewercarbon atoms or the cyclic or saturated aliphatic cyclic alcohols andacids of 5 to 10 carbon atoms. Particularly preferred aliphatic estersare those derived from lower alkyl acids and alcohols. Also preferredare the phenyl or lower alkyl phenyl esters.

Amides has the meaning classically accorded that term in organicchemistry. In this instance it includes the unsubstituted amides and allaliphatic and aromatic mono- and di- substituted amides. Unless statedotherwise in this application, preferred amides are the mono- anddi-substituted amides derived from the saturated aliphatic radicals often or fewer carbon atoms or the cyclic or saturated aliphatic-cyclicradicals of 5 to 10 carbon atoms. Particularly preferred amides arethose derived from substituted and unsubstituted lower alkyl amines.Also preferred are mono- and disubstituted amides derived from thesubstituted and unsubstituted phenyl or lower alkylphenyl amines.Unsubstituted amides are also preferred.

Acetals and ketals include the radicals of the formula-CK where K is(--OR)₂. Here, R is lower alkyl. Also, K may be --OR₇ O-- where R₇ islower alkyl of 2-5 carbon atoms, straight chain or branched.

A pharmaceutically acceptable salt may be prepared for any compounds inthis invention having a functionality capable of forming such salt, forexample an acid functionality. A pharmaceutically acceptable salt is anysalt which retains the activity of the parent compound and does notimpart any deleterious or untoward effect on the subject to which it isadministered and in the context in which it is administered.

Pharmaceutically acceptable salts may be derived from organic orinorganic bases. The salt may be a mono or polyvalent ion. Of particularinterest are the inorganic ions, sodium, potassium, calcium, andmagnesium. Organic salts may be made with amines, particularly ammoniumsalts such as mono-, di- and trialkyl amines or ethanol amines. Saltsmay also be formed with caffeine, tromethamine and similar molecules.Where there is a nitrogen sufficiently basic as to be capable of formingacid addition salts, such may be formed with any inorganic or organicacids or alkylating agent such as methyl iodide. Preferred salts arethose formed with inorganic acids such as hydrochloric acid, sulfuricacid or phosphoric acid. Any of a number of simple organic acids such asmono-, di- or tri- acid may also be used.

Some of the compounds of the present invention may have trans and cis (Eand Z) isomers. In addition, the compounds of the present invention maycontain one or more chiral centers and therefore may exist inenantiomeric and diastereomeric forms. The scope of the presentinvention is intended to cover all such isomers per se, as well asmixtures of cis and trans isomers, mixtures of diastereomers and racemicmixtures of enantiomers (optical isomers) as well. In the presentapplication when no specific mention is made of the configuration (cis,trans or R or S) of a compound (or of an asymmetric carbon) then amixture of such isomers, or either one of the isomers is intended. In asimilar vein, when in the chemical structural formulas of thisapplication a straight line representing a valence bond is drawn to anasymmetric carbon, then isomers of both R and S configuration, as wellas their mixtures are intended. Defined stereochemistry about anasymmetric carbon is indicated in the formulas (where applicable) by asolid triangle showing β configuration, or by a hashed line showing αconfiguration.

Referring now to the nomenclature used in naming the compounds of theinvention and intermediate compounds leading thereto, two differentsystems for numbering the tetrahydronaphthalene ring are demonstrated asshown by the structural formulas of Compounds F, G and 1. Compound 1 andCompounds F and G are exemplary intermediates utilized in the synthesisof the compounds of the invention. The numbering systems illustratedhere will not only be readily apparent to those skilled in the art, butwill be readily understood as it is applied in the ensuing descriptionof the compounds of the invention and of intermediates utilized forobtaining the compounds of the invention. ##STR4##

With reference to the symbol Y in Formula 5, the preferred compounds ofthe invention are those where Y is phenyl, pyridyl, thienyl or furyl.Even more preferred are compounds where Y is phenyl or pyridyl. As faras substititutions on the Y (phenyl) and Y (pyridyl) groups areconcerned, compounds are preferred where the phenyl group is 1,4 (para)substituted, and where the pyridine ring is 2,5 substituted.(Substitution in the 2,5 positions in the "pyridine" nomenclaturecorresponds to substitution in the 6-position in the "nicotinic acid"nomenclature.) In the preferred compounds of the invention there is nooptional R₂ substituent on the Y group.

The A-B group of the preferred compounds is (CH₂)_(n) -COOH or (CH₂)_(n)-COOR₈, where R₈ is defined as above. Even more preferably n is zero andR₈ is lower alkyl.

The aromatic portion of the tetrahydronaphthalene moiety is preferablysubstituted only by the acetylene function. In other words, in thepreferred compounds there is no R₂ substituent (other than hydrogen).Similarly, in the preferred compounds of the invention there is no R₃substituent (other than hydrogen). The R₁ substituent of the compoundsof the invention is preferably lower alkyl, and even more preferablymethyl.

In the preferred compounds of the invention the R₁₄ groups are hydrogenor lower alkyl, even more preferably hydrogen. The presently mostpreferred compounds of the invention in accordance with Formula 5 areindicated in Table 1 below, with reference to Formula 5A, and thesynthesis of these compounds is described in the Specific Examples.##STR5##

                  TABLE 1                                                         ______________________________________                                        Compound No.       R.sub.14                                                                             R.sub.8                                             ______________________________________                                        56                 H      Et                                                  57                 H      H                                                   ______________________________________                                    

Modes of Administration

The compounds of this invention may be administered systemically ortopically, depending on such considerations as the condition to betreated, need for site-specific treatment, quantity of drug to beadministered, and numerous other considerations.

In the treatment of dermatoses, it will generally be preferred toadminister the drug topically, though in certain cases such as treatmentof severe cystic acne or psoriasis, oral administration may also beused. Any common topical formulation such as a solution, suspension,gel, ointment, or salve and the like may be used. Preparation of suchtopical formulations are well described in the art of pharmaceuticalformulations as exemplified, for example, Remington's PharmaceuticalScience, Edition 17, Mack Publishing Company, Easton, Pa. For topicalapplication, these compounds could also be administered as a powder orspray, particularly in aerosol form. If the drug is to be administeredsystemically, it may be confected as a powder, pill, tablet or the likeor as a syrup or elixir suitable for oral administration. Forintravenous or intraperitoneal administration, the compound will beprepared as a solution or suspension capable of being administered byinjection. In certain cases, it may be useful to formulate thesecompounds by injection. In certain cases, it may be useful to formulatethese compounds in suppository form or as extended release formulationfor deposit under the skin or intramuscular injection.

Other medicaments can be added to such topical formulation for suchsecondary purposes as treating skin dryness; providing protectionagainst light; other medications for treating dermatoses; medicamentsfor preventing infection, reducing irritation, inflammation and thelike.

Treatment of dermatoses or any other indications known or discovered tobe susceptible to treatment by retinoic acid-like compounds will beeffected by administration of the therapeutically effective dose of oneor more compounds of the instant invention. A therapeutic concentrationwill be that concentration which effects reduction of the particularcondition, or retards it expansion. In certain instances, the compoundpotentially may be used in prophylactic manner to prevent onset of aparticular condition.

A useful therapeutic or prophylactic concentration will vary fromcondition to condition and in certain instances may vary with theseverity of the condition being treated and the patient's susceptibilityto treatment. Accordingly, no single concentration will be uniformlyuseful, but will require modification depending on the particularitiesof the disease being treated. Such concentrations can be arrived atthrough routine experimentation. However, it is anticipated that in thetreatment of, for example, acne, or similar dermatoses, that aformulation containing between 0.01 and 1.0 milligrams per mililiter offormulation will constitute a therapeutically effective concentrationfor total application. If administered systemically, an amount between0.01 and 5 mg per kg per day of body weight would be expected to effecta therapeutic result in the treatment of many diseases for which thesecompounds are useful.

Assay of Retinoid-like Biological Activity

The retinoic acid-like activity of these compounds is confirmed throughthe classic measure of retinoic acid activity involving the effects ofretinoic acid on ornithine decarboxylase. The original work on thecorrelation between retinoic acid and decrease in cell proliferation wasdone by Verma & Boutwell, Cancer Research, 1977, 37,2196-2201. Thatreference discloses that ornithine decarboxylase (ODC) activityincreased precedent to polyamine biosynthesis. It has been establishedelsewhere that increases in polyamine synthesis can be correlated orassociated with cellular proliferation. Thus, if ODC activity could beinhibited, cell hyperproliferation could be modulated. Although allcases for ODC activity increases are unknown, it is known that12-0-tetradecanoylphorbol-13-acetate (TPA) induces ODC activity.Retinoic acid inhibits this induction of ODC activity by TPA. An assayessentially following the procedure set out in Cancer Research:1662-1670,1975 may be used to demonstrate inhibition of TPA induction ofODC by compounds of this invention. Activity of exemplary compounds ofthe present invention in the above-described ODC assay is disclosed inTable 2 which provides the IC₈₀ concentration for the respectiveexemplary compound. ("IC₈₀ " is that concentration of the test compoundwhich causes 80% inhibition in the ODC assay. By analogy, "IC₆₀, forexample, is that concentration of the test compound which causes 60%inhibition in the ODC assay.)

                  TABLE 2                                                         ______________________________________                                        Compound #    IC.sub.80 conc (nmols)                                          ______________________________________                                        56            50.10                                                           ______________________________________                                    

SPECIFIC EMBODIMENTS

The compounds of this invention can be made by the synthetic chemicalpathways illustrated here. The synthetic chemist will readily appreciatethat the conditions set out here are specific embodiments which can begeneralized to any and all of the compounds of the present invention.##STR6##

Referring now to Reaction Scheme 1 a synthetic route leading toprecursors to the compounds of the invention is illustrated. Inaccordance with this scheme, a 6- or 7-bromo substituted3,4-dihydronaphthalen-1(2H)-one (numbering as shown for Compound G) ofFormula 10 is the starting material. The compounds of Formula 10 alreadycarry the desired R₁, R₂ and R₃ substituents, as these are defined abovein connection with Formula 5. The compounds of Formula 10 are reactedwith trimethylsilylacetylene to provide the 6- or7-trimethylsilylethynyl- substituted 3,4-dihydronaphthalen-1(2H)-onecompounds of Formula 11. The reaction with trimethylsilylacetylene istypically conducted under heat (approximately 100° C.) in the presenceof cuprous iodide, a suitable catalyst, typically having the formulaPd(PPh₃)₂ Cl₂, an acid acceptor (such as triethylamine) under an inertgas (argon) atmosphere. Typical reaction time is approximately 24 hours.The 6- or 7-(trimethylsilyl)ethynyl- substituted3,4-dihydro-naphthalen-1(2H)-one compounds of Formula 11 are thenreacted with base (potassium hydroxide or potassium carbonate) in analcoholic solvent, such as methanol, to provide the 6- or 7-ethynylsubstituted 3,4-dihydro-1-naphthalen-1(2H)ones of Formula 12. Compoundsof Formula 12 are then coupled with the aromatic or heteroaromaticreagent X₁ -Y(R₂)-A-B' (Formula 9) in the presence of cuprous iodide, asuitable catalyst, typically Pd(PPh₃)₂ Cl₂, an acid acceptor, such astriethylamine, under inert gas (argon) atmosphere. Alternatively, a zincsalt (or other suitable metal salt) of the compounds of Formula 12 canbe coupled with the reagents of Formula 9 in the presence of Pd(PPh₃)₄or similar complex. Typically, the coupling reaction with the reagent X₁-Y(R₂)-A-B' (Formula 9) is conducted at room or moderately elevatedtemperature. Generally speaking, coupling between an ethynylarylderivative or its zinc salt and a halogen substituted aryl or heteroarylcompound, such as the reagent of Formula 9, is described in U.S. Pat.No. 5,264,456, the specification of which is expressly incorporatedherein by reference. The compounds of Formula 13 are precursors tocompounds of the invention or a derivative thereof protected in the B'group, from which the protecting group can be readily removed byreactions well known in the art. The compounds of Formula 13 can also beconverted into further precursor compounds to the invention by suchreactions and transformations which are well known in the art. Suchreactions are indicated in Reaction Scheme 1 by conversion into"homologs and derivatives". One such conversion which can be employedfor the synthesis of several exemplary compounds of this invention issaponification of an ester group (when B or B' is an ester) to providethe free carboxylic acid or its salt.

The halogen substituted aryl or heteroaryl compounds of Formula 9 can,generally speaking, be obtained by reactions well known in the art. Anexample of such compound is ethyl 4-iodobenzoate which is obtainable,for example, by esterification of 4-iodobenzoic acid. Another example isethyl 6-iodonicotinoate which can be obtained by conducting a halogenexchange reaction on 6-chloronicotinic acid, followed by esterification.Even more generally speaking, regarding derivatization of compounds ofFormula 13 and/or the synthesis of aryl and heteroaryl compounds ofFormula 9 which can thereafter be reacted with compounds of Formula 12to eventually lead to compounds of the invention, the following wellknown and published general principles and synthetic methodology can beemployed.

Carboxylic acids are typically esterified by refluxing the acid in asolution of the appropriate alcohol in the presence of an acid catalystsuch as hydrogen chloride or thionyl chloride. Alternatively, thecarboxylic acid can be condensed with the appropriate alcohol in thepresence of dicyclohexylcarbodiimide and dimethylaminopyridine. Theester is recovered and purified by conventional means. Acetals andketals are readily made by the method described in March, "AdvancedOrganic Chemistry," 2nd Edition, McGraw-Hill Book Company, p 810).Alcohols, aldehydes and ketones all may be protected by formingrespectively, ethers and esters, acetals or ketals by known methods suchas those described in McOmie, Plenum Publishing Press, 1973 andProtecting Groups, Ed. Greene, John Wiley & Sons, 1981.

To increase the value of n in the compounds of Formula 9 beforeaffecting the coupling reaction of Reaction Scheme 1 (where suchcompounds corresponding to Formula 9 are not available from a commercialsource) aromatic or heteroaromatic carboxylic acids are subjected tohomologation by successive treatment under Arndt-Eistert conditions orother homologation procedures. Alternatively, derivatives which are notcarboxylic acids may also be homologated by appropriate procedures. Thehomologated acids can then be esterified by the general procedureoutlined in the preceding paragraph.

Compounds of Formula 9, (or other intermediates, or of the invention, asapplicable) where A is an alkenyl group having one or more double bondscan be made for example, by synthetic schemes well known to thepracticing organic chemist; for example by Wittig and like reactions, orby introduction of a double bond by elimination of halogen from analpha-halo-arylalkyl-carboxylic acid, ester or like carboxaldehyde.Compounds of Formula 9 (or other intermediates, or of the invention, asapplicable) where the A group has a triple (acetylenic) bond can be madeby reaction of a corresponding aromatic methyl ketone with strong base,such as lithium diisopropyl amide, reaction with diethyl chlorophosphateand subsequent addition of lithium diisopropyl amide.

The acids and salts derived from compounds of Formula 13 (or otherintermediates or compounds of the invention, as applicable) are readilyobtainable from the corresponding esters. Basic saponification with analkali metal base will provide the acid. For example, an ester ofFormula 13 (or other intermediates or compounds of the invention, asapplicable) may be dissolved in a polar solvent such as an alkanol,preferably under an inert atmosphere at room temperature, with about athree molar excess of base, for example, lithium hydroxide or potassiumhydroxide. The solution is stirred for an extended period of time,between 15 and 20 hours, cooled, acidified and the hydrolysate recoveredby conventional means.

The amide may be formed by any appropriate amidation means known in theart from the corresponding esters or carboxylic acids. One way toprepare such compounds is to convert an acid to an acid chloride andthen treat that compound with ammonium hydroxide or an appropriateamine. For example, the acid is treated with an alcoholic base solutionsuch as ethanolic KOH (in approximately a 10% molar excess) at roomtemperature for about 30 minutes. The solvent is removed and the residuetaken up in an organic solvent such as diethyl ether, treated with adialkyl formamide and then a 10-fold excess of oxalyl chloride. This isall effected at a moderately reduced temperature between about -10degrees and +10 degrees C. The last mentioned solution is then stirredat the reduced temperature for 1-4 hours, preferably 2 hours. Solventremoval provides a residue which is taken up in an inert organic solventsuch as benzene, cooled to about 0 degrees C. and treated withconcentrated ammonium hydroxide. The resulting mixture is stirred at areduced temperature for i - 4 hours. The product is recovered byconventional means.

Alcohols are made by converting the corresponding acids to the acidchloride with thionyl chloride or other means (J. March, "AdvancedOrganic Chemistry", 2nd Edition, McGraw-Hill Book Company), thenreducing the acid chloride with sodium borohydride (March, Ibid, pg.1124), which gives the corresponding alcohols. Alternatively, esters maybe reduced with lithium aluminum hydride at reduced temperatures.Alkylating these alcohols with appropriate alky halides under Williamsonreaction conditions (March, Ibid, pg. 357) gives the correspondingethers. These alcohols can be converted to esters by reacting them withappropriate acids in the presence of acid catalysts ordicyclohexylcarbodiimide and dimethylaminopyridine.

Aldehydes can be prepared from the corresponding primary alcohols usingmild oxidizing agents such as pyridinium dichromate in methylenechloride (Corey, E. J., Schmidt, G., Tet. Lett., 399, 1979), or dimethylsulfoxide/oxalyl chloride in methylene chloride (Omura, K., Swern, D.,Tetrahedron, 1978, 34, 1651).

Ketones can be prepared from an appropriate aldehyde by treating thealdehyde with an alkyl Grignard reagent or similar reagent followed byoxidation.

Acetals or ketals can be prepared from the corresponding aldehyde orketone by the method described in March, Ibid, p 810.

Compounds of Formula 9 (or other intermediates or of the invention, asapplicable) where B is H can be prepared from the correspondinghalogenated aromatic or hetero aromatic compounds, preferably where thehalogen is I.

With reference to the coupling reactions of the reagent X₁ -Y(R₂)-A-B'(Formula 9) shown in Reaction Scheme 1, it is noted that, generallyspeaking, this coupling reaction can be conducted with 6- or7-substituted ethynyl compounds which either already have a substituentdesired for the present invention in the 5- position or have a precursorsuitable for introduction of such desired substituent. ##STR7##

In the preferred compounds of the invention the two R₁ substituents aremethyl, and the R₂ and R₃ substituents are hydrogen. Reaction Scheme 2illustrates a synthetic process for preparing7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-l-one (Compound G) whichserves as a starting material for the synthesis of several preferredcompounds of the invention. Thus, referring now specifically to ReactionScheme 2, ethyl 3-bromophenylacetate (Compound B, made by esterificationof 3-bromophenylacetic acid) is reduced with diisobutylaluminum hydride(DIBAL-H) to yield (3-bromophenyl)acetaldehyde.(3-Bromophenyl)acetaldehyde is reacted in a Wittig reaction with(carbethoxymethylene)triphenylphosphorane to provide a mixture of E andZ ethyl 4-(3-bromophenyl)but-2-enoates. The latter compounds arehydrogenated to yield ethyl 4-(3-bromophenyl)butanoate (Compound D).Compound D is reacted with the Grignard reagent derived frommethylbromide to give the tertiary alcohol5-(3-bromophenyl)-2-methylpentan-2-ol (Compound E) (It should beapparent to those skilled in the art, that the choice of the Grignardreagent used in this reaction step determines the nature of the R₁substituent in the resulting compounds of the invention.) Compound E isthen treated with acid to cyclize it and to form6-bromo-1,2,3,4-tetrahydro-1,1-dimethylnaphthalene (Compound F).Compound F is oxidized with chromium trioxide to yield7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound G).Compound G is covered by Formula 10 and in accordance with ReactionScheme 1 serves as a starting material in the synthesis of severalpreferred compounds of the invention.

6-Bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound H) isisomeric with Compound G, and can be obtained, starting with ethyl(4-bromophenyl)acetate, in accordance with the sequence of reactionsillustrated in Reaction Scheme 2 for Compound G.

6-Bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound H) canalso be obtained in accordance with the published literature procedure:Mathur et al. Tetrahedron, 41, 1509-1516 (1985). Compound H is alsocovered by Formula 10 and serves as a starting material in the synthesisof several preferred compounds of the invention.

Starting materials for the synthetic routes outlined in Reaction Schemes1-3 where the R₂ and/or R₃ groups are other than hydrogen, can beobtained similarly to the synthesis of the starting materialsdemonstrated in Reaction Scheme 2, and/or by introducing the R₂ by aFriedel-Crafts or like reaction into the aromatic portion of thetetrahydronaphthalene nucleus. ##STR8##

Compounds of the invention are prepared by the reactions illustrated inReaction Scheme 3. In accordance with this scheme, the 5-oxo 2- or 3-(aryl or heteroaryl)ethynyl 5,6,7,8-tetrahydronaphthalene compounds ofFormula 13 (numbering as exemplified for Compound 1) are reduced in the5 position and aminated by reaction with ammonium acetate and sodiumcyanoborohydride (NaBH₃ CN). The latter reaction provides the 5-amino 2-or 3- (aryl or heteroaryl)ethynyl 5,6,7,8-tetrahydronaphthalenecompounds of Formula 36. Compounds of Formula 36 where the NH₂ group isnot substituted (R₁₄ of Formula 5 is hydrogen) comprise the presentlypreferred compounds of Formula 5. Compounds of Formula 5 where R₁₄ is analkyl, alkenyl, alkynyl or aryl group (as such groups are defined inconnection with Formula 5) are prepared by reaction of compounds ofFormula 36 with a reagent of the formula R₁₄ -X₁, where X₁ is halogen orother leaving group. When R₁₄ is an alkyl group then the reagent R₁₄ -X₁is an alkyl halide. Compounds of Formula 36 are reacted with an equalamount of an acylating agent, such as an acyl chloride (R₈ COCl) toyield compounds of Formula 5 which are amides (R₁₄ represents R₈ CO inFormula 5). The compounds of Formula 36 and of Formula 5 can beconverted into further homologs and derivatives by reactions well knownto the practicing organic chemist, as is described above in connectionwith compounds of Formula 13.

Compounds of Formula 5 where R₁₄ is alkyl, alkenyl, alkynyl or arylgroup (as such groups are defined in connection with Formula 5) can alsobe obtained from the 5-oxo 2- or 3- (aryl or heteroaryl)ethynyl5,6,7,8-tetrahydronaphthalene compounds of Formula 13 by reactingcompounds of Formula 13 with the corresponding amine (R₁₄ NH₂) andthereafter reducing the resulting imine compounds with hydrogen or othersuitable reducing agent. A second R₁₄ group which is alkyl, alkenyl,alkynyl or aryl, or which is R₈ CO (acyl) can be introduced into thelatter compounds by reaction with the reagent R₁₄ -X₁ (X₁ is a leavinggroup), or R₈ COCl.

In addition to the synthetic steps described above, the compounds ofFormula 5 can also be obtained, generally speaking, by first forming the5-amino, 5-alkylamino or 5-acylamido derivative from the ketonecompounds of Formula 10 (see Reaction Scheme 1) and thereafterperforming the synthetic steps of replacing the 6 or 7-bromosubstituents in these compounds with an ethynyl group, and subsequentlycoupling the ethynyl compounds with the reagent X₁ -Y(R₂)-A-B' (Formula9).

SPECIFIC EXAMPLES Ethyl (4-bromophenyl)acetate (Compund A)

A solution of 43 g (200 mmol) of 4-bromophenylacetic acid and 0.2 g ofconc. H₂ SO₄ in 470 ml of ethanol was refluxed for 16 hours. Thereaction mixture was cooled to ambient temperature, stirred with 6 g ofsolid K₂ CO₃ for 30 minutes and then filtered. The filtrate wasconcentrated in vacuo, diluted with Et₂ O (200 ml ), washed with 10%aqueous NaHCO₃ (10 ml ) and brine (10 ml), dried over MgSO₄ andconcentrated in vacuo to give the title compound as a colorless oil.

PMR (CDCl₃): δ 1.25 (3H, t, J=7.0 Hz), 3.56 (2H, s), 4.15 (2H, q, J=7.0Hz), 7.16 (2H, d, J=8.4 Hz), 7.45 (2H, d, J=8.4 Hz) .

Ethyl (3-bromophenyl)acetate (Compound B)

Employing the same general procedure as for the preparation of ethyl(4-bromophenyl)acetate (Compound A), 100 g (463 mmol) of3-bromophenylacetic acid was converted into the title compound (yellowoil) using 2 g of conc. H₂ SO₄ and 500 ml of ethanol.

PMR (CDCl₃): δ 1.26 (3H, t, J=7.0 Hz), 3.56 (2H, s), 4.16 (2H, q, J=7.0Hz), 7.16-7.26 (2H, m), 7.38-7.46 (2H, m).

Ethyl 4- (4-bromophenyl)butanoate (Compound C)

To a cold solution (-78° C.) of 15 g (62 mmol) of ethyl (4-bromophenyl)acetate (Compound A) in 150 ml of CH₂ Cl₂ was added dropwise (over aspan of 1 hour) 65 ml (65 mmol) of diisobutylaluminum hydride (DIBAL-H,1M solution in hexane). After the DIBAL-H addition was complete, thereaction was stirred at -78 ° C. for an additional hour. The reactionwas quenched by the dropwise addition of methanol (10 ml), followed bywater (10 ml) and 10% HCl (40 ml). The mixture was then warmed to 0° C.stirred for 10 minutes and then washed with water (15 ml), 10% aqueousNaHCO₃ (10 ml) and brine (10 ml). The organic phase was dried over MgSO₄and the solvent distilled off at ambient temperature to give crude(4-bromophenyl)acetaldehyde. To a cold solution (0 ° C.) of this crudealdehyde in 150 ml of CH₂ Cl₂ was added a solution of 26 g (74.6 mmol)of (carbethoxymethylene)triphenylphosphorane in 50 ml of CH₂ C₂. Themixture was stirred for 16 hours, concentrated in vacuo and purified byflash chromatography (silica, 10% EtOAc-hexane) to give ethyl4-(4-bromophenyl)but-2-enoate as a mixture of E:Z isomers. This isomericmixture was dissolved in 150 ml of EtOAc and hydrogenated over 1 g of10% Pd/C for 6 hours. The catalyst was filtered off and the filtrateconcentrated in vacuo to give the title compound as a white solid.

PMR (CDCl₃): δ 1.26 (3H, t, J=7.1 Hz), 1.88-1.99 (2H, m), 2.31 (2H, t,J=7.5 Hz), 2.61 (2H, t, J=7.5 Hz), 4.28 (2H, q, J =7.1 Hz), 7.05 (2H, d,J=8.4 Hz), 7.40 (2H, d, J=8.4 Hz).

Ethyl 4- (3-bromophenyl) butanoate (Compound D)

Employing the same general multistep preparation as for ethyl4-(4-bromophenyl)butanoate (Compound C), 60 g (246 mmol) of ethyl(3-bromophenyl)acetate (Compound B) was converted into the titlecompound (oil) using 255 ml (255 mmol) of diisobutylaluminum hydride(DIBAL-H, 1M in hexane), 85.8 g (250 mmol) of(carbethoxymethylene)triphenylphosphorane and 1.7 g of 10% Pd/C.

PMR (CDCl₃): δ 1.26 (3H, t, J=7.1 Hz), 1.89-2.00 (2H, m), 2.31 (2H, t,J=7.5 Hz), 2.63 (2H, t, J=7.2 Hz), 4.15 (2H, q, J=7.1 Hz), 7.10-7.35(4H, m).

5- (3-bromophenyl)-2-methylpentan-2-ol (Compound E)

To a cold solution (0° C.) of 17 g (63 mmol) of ethyl 4-(3-bromophenyl)butanoate (Compound D) in 40 ml of THF was added 63 ml(189 mmol) of methylmagnesium bromide (3.0M solution in THF). Thereaction was stirred at 0° C. for 2 hours, quenched by the slow additionof ice cold water (30 ml) followed by 10% HCl (30 ml) and then extractedwith Et₂ O (4×60 ml). The combined organic layer was washed with 10%aqueuos NaHCO₃ (10 ml), water (10 ml) and brine (10 ml), dried overMgSO₄ and concentrated in vacuo. Purification by Kugelrohr distillationgave the title compound as a colorless oil.

PMR (CDCl₃): δ 1.20 (6H, s), 1.43-1.55 (2H, m), 1.62-1.78 (2H, m), 2.60(2H, t, J=6.0 Hz), 7.10-7.41 (4H, m).

6-Bromo-1,2,3,4-tetrahydro-1,1-dimethylnaphthalene (Compound F)

15.0 g (58.3 mmol) of 5- (3-bromophenyl ) -2-methylpentan-2-ol (CompoundE) was cooled to 0° C. and then 2.8 ml of conc. H₂ SO₄ was added. Themixture was stirred for 2.5 hours, diluted with water (20 ml) andextracted with Et₂ O (3×40 ml). The combined organic layers were washedwith water, sat. aqueous NaHCO₃ and brine, dried over MgSO₄ andconcentrated in vacuo. Purification by Kugelrohr distillation gave thetitle compound as a colorless oil.

PMR (CDCl₃): δ 1.25 (6H, s) , 1.61-1.66 (2H, m) , 1.74-1.82 (2H, m),2.73 (2H, t, J=6.0 Hz), 7.16-7.26 (3H, m).

7-Bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound G)

To a cold mixture (0° C.) of 209 g (200 mmol) of chromium trioxide, 100ml (1.06 mol) of acetic anhydride and 200 ml (3.5 tool) of acetic acidwas added a solution of 10 g (41.8 mmol) of6-bromo-1,2,3,4-tetrahydro-1,1-dimethylnaphthalene (Compound F) in 125ml of benzene. The reaction mixture was stirred for 1 hour, quenchedwith ice cold water and extracted with Et₂ O (3×100 ml). The organiclayer was dried over MgSO₄, concentrated in vacuo, and purified bycolumn chromatography (silica, 10% EtOAc-hexane) to give the titlecompound as a white solid.

PMR (CDCl₃): δ 1.28 (6H, s), 2.01 (2H, t, J=6.0 Hz), 2.72 (2H, t,J=6.0Hz), 7.31 (1H, d, J=9.0 Hz), 7.61 (1H, dd, J=3.0, 9.0 Hz), 8.11(1H, d, J=3.0 Hz).

6-Bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H) -one (Compound H)

Employing a published procedure (Mathur, N. C.; Snow, M. S. ; Young, K.M.; and Pincock, J. A. Tetrahedron, 41, 1509-1516 (1985)), ethyl4-(4-bromophenyl)butanoate (Compound C) was converted into the titlecompound. Alternatively, the title compound can be obtained usingsimilar reactions that were used to convert ethyl 4- (3-bromophenyl)butanoate (Compound D) into7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H) -one (Compound G) .

6-Ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H) -one (Compound K)

To a solution (flushed for 15 minutes with a stream of argon) of 13.55 g(53.8 mmol) of 6-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H) -one(Compound H) in 280 ml of triethylamine was added 1.87 g (2.66 mmol) ofbis(triphenylphosphine)palladium (II) chloride and 0.53 g (2.66 mmol) ofcuprous iodide. The solution mixture was flushed with argon for 5minutes and then 100 ml (938.7 mmol) of trimethylsilyl acetylene wasadded. The reaction mixture was sealed in a pressure tube and placed ina preheated oil bath (100° C.) for 24 hours. The reaction mixture wasthen filtered through Celite, washed with Et₂ O and the filtrateconcentrated in vacuo to give crude6-(2-trimethylsilyl)ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one.To a solution of this crude TMS-acetylenic compound in 50 ml of methanolwas added 2.8 g (20.3 mmol) of K₂ CO₃. The mixture was stirred for 8hours at ambient temperature and then filtered. The filtrate wasconcentrated in vacuo, diluted with Et₂ O (100 ml), washed with water(10 ml), 10% HCl (10 ml) and brine (10 ml), dried over MgSO₄ andconcentrated in vacuo. Purification by column chromatography (silica,10% EtOAc-hexane) yielded the title compound as a white solid.

PMR (CDCl₃): δ 1.38 (6H, s), 2.01 (2H, t, J=7.1 Hz), 2.72 (2H, t, J=7.1Hz), 3.24 (1H, s), 7.39 (1H, dd, J=1.5, 8.1 Hz), 7.54 (1H, d, J=1.5 Hz),7.91 (1H, d, J=8.1 Hz).

7-Ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound L)

Employing the same general procedure as for the preparation of6-ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound K), 7 g(27.6 mmol) of 7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one(Compound G) was converted into the title compound using 39 ml (36.6mmol) of trimethylsilyl acetylene, 0.97 g (1.3 mmol) ofbis(triphenylphosphine)palladium(II) chloride, 0.26 g (1.3 mmol) ofcuprous iodide and 0.6 g (4.3 mmol) of K₂ CO₃.

PMR (CDCl₃): δ 1.39 (6H, s), 2.02 (2H, t, J=7.0 Hz), 2.73 (2H, t, J=7.0Hz), 3.08 (1H, s), 7.39 (1H, d, J=8.2 Hz), 7.61 (1H, dd, J=1.8 , 8.2Hz), 8.14 (1H, d, J=9 1.8 Hz).

Ethyl-4-iodobenzoate

To a suspension of 10 g (40.32 mmol) of 4-iodobenzoic acid in 100 mlabsolute ethanol was added 2 ml thionyl chloride and the mixture wasthen heated at reflux for 3 hours. Solvent was removed in vacuo and theresidue was dissolved in 100 ml ether. The ether solution was washedwith saturated NaHCO₃ and saturated NaCl solutions and dried (MgSO₄).Solvent was then removed in vacuo and the residue Kugelrohr distilled(100 degrees C.; 0.55 mm) to give the title compound as a colorless oil,PMR (CDCl₃): δ 1.42 (3H, t, J˜7 Hz), 4,4 (2H, q, J˜7 Hz), 7.8 (4H).

Ethyl 6-chloronicotinate

A mixture of 15.75 g (0.1 mol) 6-chloronicotinic acid, 6.9 g (0.15 mol)ethanol, 22.7 g (0.11 mol) dicyclohexylcarbodiimide and 3.7 gdimethylaminopyridine in 200 ml methylene chloride was heated at refluxfor 2 hours. The mixture was allowed to cool, solvent removed in vacuoand the residue subjected to flash chromatography to give the titlecompound as a low-melting white solid. PMR (CDCl₃): δ 1.44 (3H, t, J˜6.2Hz) 4.44 (2H, q, J˜4.4 Hz), 7.44 (1H, d, J-8.1 Hz), 8.27 (1H, dd, J-8.1Hz, 3 Hz), 9.02 (1H, d, J-3 Hz).

6-Iodonicotinic acid

To 27.97 g (186.6 mmol) of sodium iodide cooled to -78° C. was added121.77 g (71.6 ml, 952.0 mmol) of hydriodic acid (57 wt %). The reactionmixture was allowed to warm slightly with stirring for 5 minutes, andthen 30.00 g (190.4 mmol) of 6-chloronicotinic acid was added. Theresulting mixture was allowed to warm to room temperature with stirringand then heated at 120°-125° C. in an oil bath for 42 hours. A darkbrown layer formed above the yellow solid material. The reaction mixturewas allowed to cool to room temperature and then poured into acetone(chilled to 0° C.). The resultant yellow solid was collected byfiltration, washed with 200 ml of 1N NaHSO₃ solution, and dried in highvacuum (3 mm Hg) to give the title compound as a pale yellow solid.

PMR (DMSO-d₆): δ 7.90 (1H, dd, J=8.1, 2 Hz), 7.99 (1H, d, J=8.1 Hz),8.80 (1H, d, J=2.Hz).

Ethyl 6-iodonicotinate

To a suspension of 23.38 g (94.2 mmol) of 6-iodonicotinic acid in 100 mlof dichloromethane was added a solution of 19.86 g (103.6 mmol) of1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride in 250 ml ofdichloromethane. To this suspension was added 12.40 g (15.8 ml, 269.3mmol) of ethanol (95%) and 1.15 g (9.4 mmol) of 4-dimethylaminopyridine.The resulting solution mixture was then heated at 50° C. in an oil bathfor 24.5 hours, concentrated in vacuo, partitioned between 200 ml ofwater and 250 ml of ethyl ether, and the layers were separated. Theaqueous phase was washed with 2×150 ml portions of ethyl ether. Allorganic phases were combined, washed once with 75 ml of brine solution,dried over MgSO₄, filtered and concentrated in vacuo to a yellow solid.Purification by flash chromatography (silica, 10% ethyl acetate inhexane) yielded the title compound as a white solid.

PMR (CDCl₃): δ 1.41 (3H, t, J=7.1 Hz), 4.41 (2H, q, J=7.1 Hz), 7.85 (1H,d, J=8.2 Hz), 7.91 (1H, dd, J= 8.2, 2.1 Hz), 8.94 (1H, d, J=2.1 Hz).

Ethyl 4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl)ethynyl]benzoate (Compound 1)

To a solution of 8.8 g (47.8 mmol) of6-ethynyl-1,2,3,4-tetrahydro-4,4-dimethylnaphthalen-1-one (Compound K)flushed for 15 minutes with a stream of argon, and 13.2 g (47.8 mmol) ofethyl 4-iodobenzoate in 200 ml of triethylamine was added 1.1 g (1.6mmol) of bis(triphenylphosphine) palladium(II) chloride and 0.30 g (1.6mmol) of cuprous iodide. The solution mixture was flushed with argon for5 minutes and then stirred at ambient temperature for 18 hours. Thereaction mixture was filtered through Celite and the filtrateconcentrated in vacuo. Purification by flash chromatography (silica, 10%EtOAc-hexane) yielded the title compound as a white solid.

PMR (CDCl₃): δ 1.41 (3H, t, J=7.2 Hz), 1.43 (6H, s), 2.04 (2H, t, J=7.0Hz), 2.75 (2H, t, J=7.0 Hz), 4.40 (2H, q, J=7.2 Hz), 7.46 (1H, dd,J=1.5, 8.1 Hz), 7.60 (1H, d, J=1.5 Hz), 7.63 (2H, d, J=8.4 Hz), 8.01(1H, d, J=8.1 Hz), 8.05 (2H, d, J=8.4 Hz).

Ethyl 4- [(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-3-yl )ethynyl]benzoate (Compound 2)

Employing the same general procedure as for the preparation of ethyl4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl )ethynyl]benzoate(Compound 1), 4 g (21.7 mmol) of 7-ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound L) was converted into the titlecompound using 6 g (21.7 mmol) of ethyl 4-iodobenzoate, 5 g (7.2 mmol)of bis(triphenylphosphine)palladium(II) chloride and 1.4 g (7.2 mmol) ofcuprous iodide.

PMR (CDCl₃): δ 1.41 (3H, t, J=7.2 Hz), 1.41 (6H, s), 2.04 (2H, t, J=6.5Hz), 2.76 (2H, t, J=6.5 Hz), 4.40 (2H, q, J=7.2 Hz), 7.44 (1H, d, J=8.2Hz), 7.59 (2H, d, J=8.4 Hz), 7.68 (1H, dd, J=1.8, 8.2 Hz), 8.04 (2H, d,J=8.4 Hz), 8.15 (1H, d, J=1.8 Hz).

Ethyl6-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-3-yl)ethynyl]nicotinate(Compound 3)

Employing the same general procedure as for the preparation of ethyl 4 -[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl) ethynyl]benzoate(Compound 1) , 606 mg (3.48 mmol) of7-ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound K) wasconverted into the title compound using 964 mg (3.48 mmol) of ethyl6-iodonicotinate, 122 mg (0.17 mmol) of bis(triphenylphosphine)palladium(II) chloride and 9.5 mg (0.17 mmol) ofcuprous iodide.

PMR (CDCl₃): δ 1.41 (6H, s) , 1.43 (3H, t, J=7.1 Hz), 2.05 (2H, t, J=7.1Hz), 2.76 (2H, t, J=7.1 Hz), 4.43 (2H, q, J=7.1 Hz), 7.46 (1H, d, J=8.2Hz), 7.60 (1H, d, J=7.8 Hz), 7.75 (1H, dd, J=1.9, 8.2 Hz), 8.27 (1H, d,J=1.9 Hz), 8.30 (1H, dd, J=2.0, 7.8 Hz), 9.22 (1H, br s).

Ethyl 6-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl)ethynyl]nicotinate (Compound 5)

Employing the same general procedure as for the preparation of ethyl4-[5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl) ethynyl]benzoate(Compound 1) , 422 mg (2.1 mmol) of6-ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound L) wasconverted into the title compound using 202 mg (0.73 mmol) of ethyl6-iodonicotinate, 168 mg (0.24 mmol) ofbis(triphenylphosphine)palladium(II) chloride and 45.7 mg (0.24 mmol) ofcuprous iodide.

PMR (CDCl₃): δ 1.40 (6H, s), 1.42 (3H, t, J=7.1 Hz), 2.04 (2H, t, J=6.0Hz), 2.74 (2H, t, J=6.0 Hz), 4.43 (2H, q, J=7.1 Hz), 7.51 (1H, d, J=8.4Hz), 7.63 (1H, d, J=8.4 Hz), 7.70 (1H, s), 8.01 (1H, d, J=8.1 Hz), 8.30(1H, d, J=8.1 Hz), 9.22 (1H, s).

4- [(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl)ethynyl]benzoicacid (Compound 7)

To a suspension of 0.30 g (0.87 mmol) of ethyl4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl)ethynyl]benzoate(Compound 1) in 4 ml of THF and 2 ml of ethanol was added 2 ml (2retool) of LiOH (1N aqueous solution). The reaction mixture was stirredat room temperature for 4 hours, concentrated in vacuo to near dryness,partitioned between EtOAc and 1 ml of water and acidified to pH 4 with10% HCl. The aqueous layer was extracted with EtOAc and then the organiclayer was dried over Na₂ SO₄ and concentrated in vacuo to give the titlecompound as a light yellow solid.

PMR (DMSO-d₆): δ 1.39 (6H, s), 1.98 (2H, t, J=7.0 Hz), 2.70 (2H, t,J=7.0 Hz), 7.54 (1H, dd, J=1.5, 8.1 Hz), 7.73 (2H, d, J=8.4 Hz), 7.77(1H, d, J=1.5 Hz), 7.90 (1H, d, J=8.1 Hz), 8.00 (2H, d, J=8.4 Hz).

[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-3-yl)ethynyl]benzoic acid(Compound 8 )

Employing the same general procedure as for the preparation of 4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl ) ethynyl]benzoicacid (Compound 7 ) , 500 mg (1.45 mmol) of ethyl 4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-3-yl) ethynyl]benzoate (Compound 2) was converted into the title compound using 4 ml (4 mmol) of LiOH (1Naqueous solution).

PMR (DMSO-d₆): δ 1.37 (6H, s), 1.99 (2H, t, J=6.9 Hz), 2.71 (2H, t,J=6.9 Hz), 7.64 (1H, d, J=8.2 Hz), 7.70 (2H, d, J=8.3 Hz), 7.80 (1H, dd,J=2.0, 8.2 Hz) , 7.98 (3H, m) .

6-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-3-yl)ethynyl]nicotinicacid (Compound 44)

Employing the same general procedure as for the preparation of4-[[5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl]ethynyl]benzoicacid (Compound 7), 300 mg (0.86 mmol) of ethyl6-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-3 -yl)ethynyl]nicotinate(Compound 3) was converted into the title compound (pale yellow solid)using 8.6 ml (8.6 mmol) of LiOH (1M aqueous solution) .

PMR (DMSO-d₆): PMR δ 1.38 (6H, s), 1.99 (2H, t, J=6 Hz), 2.72 (2H, t,J=6 Hz), 7.68 (1H, d, J=8.2 Hz), 7.82 (1H, d, J=8.5 Hz), 7.86 (1H, dd,J=2, 8.2 Hz), 8.04 (1H, d, J=2 Hz), 8.30 (1H, dd, J=1.9, 7.9 Hz), 9.07(1H, d, 1.9 Hz).

Ethyl4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-aminonaphth-3-yl)ethynyl]benzoate(Compound 56)

To a solution of 100 mg (0.3 mmol) of ethyl4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-3-yl)ethynyl]benzoate(Compound 2 ) in 5 ml of MeOH was added 922 mg (12 mmol) of ammoniumacetate and then 188 mg (3 mmol) of sodium cyanoborohydride. Thereaction mixture was refluxed for 1 hour, stirred at ambient temperaturefor 12 hours and then diluted with water (10 ml) and extracted with Et₂₀(3×30 ml). The organic layer was washed with water (5 ml) and brine (5ml), dried over MgSO₄ and concentrated in vacuo to an oil.Recrystallization from EtOAc-hexane yielded the title compound as awhite solid.

PMR (CDCl₃): δ 1.26 (3H, s), 1.31 (3H, s), 1.40 (3H, t, J=7.1 Hz),1.60-1.78 (2H, m), 1.80-1.90 (3H, m), 2.00-2.12 (1H, m), 3.94 (1H, t,J=6.0 Hz), 4.38 (2H, q, J=7.1 Hz), 7.30 (1H, d, J=8.2 Hz), 7.37 (1H, dd,J=1.7 , 8.2 Hz), 7.56 (2H, d, J=8.2 Hz), 7.62 (1H, br s) , 8.01 (2H, d,J=8.2 Hz) .

4- [(5,6,7,8-tetrahydro-8,8 -dimethyl-5-aminonaphth-3-yl)ethynyl]benzoicacid (Compound 57 )

100 mg (0.29 mmol) of ethyl4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-aminonaphth-3 -yl)ethynyl]benzoatein a mixture of THF and methanol (Compound 56) was refluxed (2 hours)with 0.5 ml (0.5 mmol) of LiOH (1M aqueous solution). Thereafter themixture was diluted with Et₂ O:EtOAc (1:1), and acidified with aqueousHCl to pH5. The organic phase was separated, washed (water and brine),dried (MgSO₄) to yield the title compound.

PMR (DMSO-d₆): δ 1.26 (3H, s), 1.31 (3H, s), 1.55-1.65(2H, m), 1.80-2.00(3H, m), 2.05-2.20 (1H, m), 4.20 (1H, br s), 7.50 (2H, br s), 7.55 (2H,d, J=8.2 Hz), 7.80 (1H, s), 7.95 (2H, d, J=8.2 Hz).

What is claimed is:
 1. A compound of the formula ##STR9## wherein R₁ ishydrogen or alkyl of 1 to 10 carbons;R₂ and R₃ are hydrogen, or alkyl of1 to 6 carbons and the substituted ethynyl group occupies either the 2or the 3 position of the tetrahydronaphthalene nucleus; m is an integerhaving the value of 0-3; o is an integer having the value 0-4; Y is aphenyl group, or heteroaryl selected from a group consisting of pyridyl,thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl,oxazolyl, and imidazolyl, said groups being optionally substituted withone or two R₂ groups; A is (CH₂)_(n) where n is 0-5, lower branchedchain alkyl having 3-6 carbons, cycloalkyl having 3-6 carbons, alkenylhaving 2-6 carbons and 1 or 2 double bonds, alkynyl having 2-6 carbonsand 1 or 2 triple bonds; B is hydrogen, COOH or a pharmaceuticallyacceptable salt thereof, COOR₈, CONR₉ R₁₀, --CH₂ OH, CH₂ OR₁₁, CH₂OCOR₁₁, CHO, CH(OR₁₂)₂, CHOR₁₃ O, --COR₇, CR₇ (OR₁₂)₂, CR₇ OR₁₃ O, ortri-lower alkylsilyl, where R₇ is an alkyl, cycloalkyl or alkenyl groupcontaining 1 to 5 carbons, R₈ is an alkyl group of 1 to 10 carbons ortrimethylsilylalkyl where the alkyl group has 1 to 10 carbons, or acycloalkyl group of 5 to 10 carbons, or R₈ is phenyl or loweralkylphenyl, R₉ and R₁₀ independently are hydrogen, an alkyl group of 1to 10 carbons, or a cycloalkyl group of 5-10 carbons, or phenyl or loweralkylphenyl, R₁₁ is lower alkyl, phenyl or lower alkylphenyl, R₁₂ islower alkyl, and R₁₃ is divalent alkyl radical of 2-5 carbons, and R₁₄is hydrogen, alkyl of 1 to 10 carbons, alkenyl of 2 to 10 carbons andhaving 1 to 3 double bond, alkynyl having 2 to 10 carbons and 1 to 3triple bonds, carbocyclic aryl selected from the group consisting ofphenyl, C₁ -C₁₀ -alkylphenyl, naphthyl, C₁ -C₁₀ -alkylnaphthyl,phenyl-C₁ -C₁₀ alkyl, naphthyl-C₁ -C₁₀ alkyl, R₁₄ is COR₈, or the twoR₁₄ groups together with the N jointly form a 5 or 6 membered ring.
 2. Acompound of claim 1 where Y is phenyl, pyridyl, thienyl or furyl.
 3. Acompound of claim 1 where Y is phenyl.
 4. A compound of claim 3 wherethe phenyl ring is 1,4 (para) substituted.
 5. A compound of claim 1where Y is pyridyl.
 6. A compound of claim 5 where the pyridyl ring issubstituted in the 2 and 5 positions.
 7. A compound of claim 1 where Yis thienyl or furyl.
 8. A compound of claim 1 where R₂ is hydrogen.
 9. Acompound of claim 1 where R₃ is hydrogen.
 10. A compound of claim 1where R₁₄ is hydrogen or lower alkyl.
 11. A compound of the formula##STR10## wherein R₁ is hydrogen or alkyl of 1 to 10 carbons;R₂ and R₃are hydrogen, or alkyl of 1 to 6 carbons and the substituted ethynylgroup occupies either the 2 or the 3 position of thetetrahydronaphthalene nucleus; m is an integer having the value of 0-3;o is an integer having the value 0-4; Y is phenyl or pyridyl, saidgroups being optionally substituted with one or two R₂ groups; A is(CH₂)_(n) where n is 0-5, lower branched chain alkyl having 3-6 carbons,cycloalkyl having 3-6 carbons, alkenyl having 2-6 carbons and 1 or 2double bonds, alkynyl having 2-6 carbons and 1 or 2 triple bonds; B ishydrogen, COOH or a pharmaceutically acceptable salt thereof, COOR₈,CONR₉ R₁₀, --CH₂ OH, CH₂ OR₁₁, CH₂ OCOR₁₁, CHO, CH(OR₁₂)₂, CHOR₁₃ O,--COR₇, CR₇ (OR₁₂)₂, CR₇ OR₁₃ O, or tri-lower alkylsilyl, where R₇ is analkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons, R₈ is analkyl group of 1 to 10 carbons or trimethylsilylalkyl where the alkylgroup has 1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, orR₈ is phenyl or lower alkylphenyl, R₉ and R10 independently arehydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group of5-10 carbons, or phenyl or lower alkylphenyl, R₁₁ is lower alkyl, phenylor lower alkylphenyl, R₁₂ is lower alkyl, and R₁₃ is divalent alkylradical of 2-5 carbons, and R₁₄ is hydrogen, alkyl of 1 to 10 carbons,or R₁₄ is COR₈.
 12. A compound of claim 11 where A is (CH₂)_(n) where nis 0-5 and where B is COOH or a pharmaceutically acceptable saltthereof, COOR₈, or CONR₉ R₁₀.
 13. A compound of claim 12 where B is COOHor a pharmaceutically acceptable salt thereof, or COOR₈ where R₈ is analkyl group of 1 to 10 carbons or trimethylsilylalkyl where the alkylgroup has 1 to 10 carbons.
 14. A compound of the formula ##STR11##wherein R₈ is hydrogen, an alkyl group of 1 to 10 carbons ortrimethylsilylalkyl where the alkyl group has 1 to 10 carbons, andR₁₄ isH or lower alkyl.
 15. A compound of claim 14 where R₁₄ is H and R₈ is Hor C₂ H₅.